1. Field of the Invention
This invention relates to a negative pressure air stream accelerator for an air cooling mechanism of an engine for forcibly cooling the inner core of an engine with atmospheric air through the engine.
2. Description of the Prior Art
An internal combustion engine of the air cooled type is known, and is particularly used frequently in an engine of small size and heat generation. Internal combustion engines of large size for automobiles frequently employ liquid cooling using coolant, such as water. Since the boiling point temperature of the liquid is lower than the heat generated from the engine so that it is less difference from the normal temperature of the engine when the engine is rotated. Thus, when the load of the engine is increased or the engine is continuously operated at a high speed, the coolant immediately arrives at the boiling point so that the engine is feasibly overheated. Another disadvantage of the liquid cooling type is that the structure is complicated, seals for preventing the liquid from leaking under temperature changes up to approximately. 100.degree. C. must be provided, coolant quantity and components must be managed, and maintenance is troublesome.
In the liquid cooled type engine, the temperature of the cooling liquid is lowered by a radiator connected to the engine, in which the heat of the cooling liquid is exchanged to the air. Atmospheric air temperature averages approximately. 20.degree. C. and approximately 50.degree. C. under the most severe conditions. This temperature is much lower than the boiling point of the cooling liquid of conventional cooled engines, and the air is available without limit.